Perl and cpanm on Bash on Ubuntu on Windows 10: Who do I report this to?

I promised a longer post on Bash on Ubuntu on Windows 10, explaining why I use it, when I don't and why I even use Windows 10, but that isn't today.

Today is me trying to figure out who to report a bug to, and how to effectively report it.

The system (called "Ubuntu on Windows" for the rest of this blog post) is Ubuntu 14.04 LTS running kinda with Windows as the kernel instead of Linux. A good thing is that, if you can apt-get install a package, you can put it on Ubuntu on Windows. I don't think you can use it if 1) it connects to the kernel (because the kernel is Windows) or 2) it pops up a window. I've heard about people using XMing to get around that, but I haven't tried it yet.

The problem is that you get what you have available with dpkg, and the perl that comes with 14.04 is 5.18, where current is 5.24. Some modules haven't been packaged, and there's usually a gap between the package version and the cpan version, so I tend to use perlbrew and use my own perl instead of system perl.

And cpan and cpanm can't build on Ubuntu on Windows. I demonstrated this by trying to install YAML::XS with cpanm. I won't include the build log, but I will link to the build log. The problem comes at lines 146, 162 and 207:

#   Failed test 'Literal Scalar'
#   at t/dump-heuristics.t line 4.
#          got: '--- '1234567890
# 
#   1234567890
# 
#   1234567890
# 
# '
# '
#     expected: '--- |
#   1234567890
#   1234567890
#   1234567890
# '

#   Failed test 'Double Quoted Scalar'
#   at t/dump-heuristics.t line 10.
#          got: '--- 'A
# 
#   B
# 
#   C
# 
# '
# '
#     expected: '--- "A\nB\nC\n"
# '
# Looks like you failed 2 tests of 2.
t/dump-heuristics.t ...... 

...

#   Failed test 'Dumping Chinese hash works'
#   at t/utf8.t line 31.
#          got: '---
# Email: boss@opcafe.net
# 地址: 新竹市 300 石坊街 37-8 號
# 店名: OpCafé
# 時間: 11:01~23:59
# 電話: '03-5277806
# 
#   0991-100087
# 
# '
# '
#     expected: '---
# Email: boss@opcafe.net
# 地址: 新竹市 300 石坊街 37-8 號
# 店名: OpCafé
# 時間: 11:01~23:59
# 電話: "03-5277806\n0991-100087\n"
# '
# Looks like you failed 1 test of 8.
t/utf8.t ................. 
Dubious, test returned 1 (wstat 256, 0x100)
Failed 1/8 subtests 

The problem involves incorrectly handling newlines, but all this works and YAML::XS installs perfectly on my personal Perl, which I demonstrate below.

$ which perl ; perl -v | head -n 5 ; perl -MYAML::XS -e "print 'Yet Another Perl Hacker'"

/home/jacoby/perl5/perlbrew/perls/perl-5.24.0/bin/perl

This is perl 5, version 24, subversion 0 (v5.24.0) built for i686-linux
(with 1 registered patch, see perl -V for more detail)

Copyright 1987-2016, Larry Wall
Yet Another Perl Hacker

So, if it's Perl on Ubuntu on Windows, and the Perl works perfectly other places (including Strawberry Perl on the same Windows 10 machine (but only in PowerShell) ) and the Ubuntu works perfectly on other places, it must be the Windows, right?

That's what I thought, too. There's a GitHub repo for Ubuntu on Windows. Well, really, it's an issue tracker for Ubuntu on Windows, because there's nothing else in there. You can't clone and build your own. But, it does put the issue tracker in a place where the natural audience for Ubuntu on Windows would go. I put in an issue, but I think I might have asked wrong. I have cleaned up my issue some, but I see no sign that anyone else has seen it.

So, what is my next step? It isn't just YAML::XS; that's just a module I wanted at the time. It isn't just cpanm; I tried with cpan, too. It is just with Windows 10. Thoughts and suggestions from the greater Perl community?